Ridley Scott has been mediocre for at least a decade now, but I am happy to hear that they will be using a lot of traditional special effects rather than CGI.
When it comes to our desire for sequels or prequels - we are looking for something that recreates the feelings we experience when watching the originals, but it is a fool's errand. Movies exist within a certain cultural context; Star Wars could only have been Star Wars in the summer of '77, and even had TPM been a good film, we still have not had that "peak experience" that we are looking for.
I hope Prometheus is a good film - but do not expect it to resonate with you like Alien or Aliens did (even if somehow it actually is as good as those films).